Apparatus for stabilizing boards emerging from gangsaws



G. A. LOFTIN Oct. 23, 1956 APPARATUS FOR STABILIZING BOARDS EMERGINGFROM GANGSAWS 2 Sheets-Sheet 1 Filed NOV. 1'?, 1954 GRADY A. LOF TINwww5/fw ATTORNEYS` G. A. LOFTIN Oct. 23, 1956 APPARATUS FOR STABILIZINGBOARDS EMERGING FROM GANGSAWS 2 sheets-shea 2 Filed Nov. 17, 1954INVENTOR GRADY A. LOF-TIN WMM ATTORNEYS 2,767,748 Patented Oct. 23, 1956APPARATUS FOR STABILIZING BOARDS EMERGING FROM GANGSAWS Grady A. Loftin,Altavista, Va., assignor to The Lane Company, Inc., Altavista, Va., acorporation of Virginia Application November 17, 1954, Serial No.469,460

8 Claims. (Cl. 143-157) This invention relates to vertical,reciprocating gangsaws, and in particular to apparatus adapted tocontrol and stabilize boards emerging therefrom during the sawingoperation.

Vertical, reciprocating gangsaws are well known and in widespread use.These devices commonly include power driven feed rolls, adapted to holdsteady the log being sawed and to feed the log through the mill.Additionally, an infeed carriage is usually employed, mounted on railsdisposed below and parallel to the infeed path of the mill, adapted tofirmly engage the rear end of a log and powered to supply a majorportion of the feed impetus thereto.

The sawed boards emerging from the gangsaw are prone to vibrate andbounce in vertical direction, especially during high speed operation andin the so-called double mills, and this condition if uncontrolled mayresult in considerable damage to the board product, or completedestruction thereof. To control the bounce of the outfed boards anoutfeed carriage is commonly utilized, mounted on rails disposed belowand parallel to the outfeed path of the mill. These devices may includehooks or similar elements designed to grip and firmly retain the leadingend of the board bundle. In high speed operation however, and in theoperation of double mills, control devices of this type are oftenineffective. To assist the outfeed carriage in controlling the boardbundle it is common to have one or more men physicaly ride the outfedboard bundle, in the attempt to hold it down and steady until the sawingoperation is completed. The utilization of these tailboys materiallyadds to the cost of operation, and yet may prove ineffective in extremecases.

It is a principal object of the present invention to provide improvedmechanical means for stabilizing boards emerging from a gangsaw, tominimize vibration and bouncing of the boards and prevent damage theretoand destruction thereof under all conditions of operation.

A further object of the invention is to provide apparatus forstabilizing boards emerging from a gangsaw, adapted to function ecientlywithout adjustment in the sawing of logs andV cants of various sizes,shapes and configurations. The invention is particularly adapted toindividually engage and prevent bouncing of all. the sawed boards,irrespective of holes, declivities or other irregularities in individualboards.

Another object of the invention is to provide a board stabilizingapparatus adapted to firmly control all boards throughout the sawingoperation by edge contact only, without materially damaging the engagededges.

.Yet another object is to provide a board stabilizing apparatusincluding power driven conveyor means to facilitate the travel of boardsoutfed by a gangsaw. Other objects will be in part evident, and in partpointed out hereinafter. The invention and the novel features thereofmay best be made clear from the following description vand theaccompanying drawings, in which:

Figure 1 is a side elevational view of a preferred embodiment of thepresent invention, disposed in operative relationship to a conventionalgangsaw indicated by dotted lines;

Figure 2 is a top plan view of the stabilizing apparatus of Figure l,partly broken away for the sake of clarity;

Figure 3 is an end elevationalview of the device of Figure l, lookingtoward the right hand end thereof, and illustrating the normal positionof its control fingers when not engaging boards, and

Figure 4 is a sectional elevational view of the device, taken on theline 4 4 of Figure 3.

Referring to the drawings in detail, Figure l illustrates a conventionalvertical, reciprocating gangsaw 10, mounted below and extending abovethe work oor 12. As will be understood, the gangsaw 10 mounts aplurality of parallel, verticaly disposed saw blades 13, which arereciprocated vertically to saw a cant or log 14 into a plurality ofboards 15 in a single pass through the mill. Normally a conventionalinfeed carriage (not shown) is disposed on the infeed vside of thegangsaw, to the left as illustrated, to engage and feed logs through themill. As will be evident, the Vertical reciprocatory sawing action ofthe blades 13 inherently tends to impart vibratory vertical movement tothe outfed boards 15, the effect of which becomes greater as the freelength of the boards increases.

To effectively stabilize the boards emerging from the mill, according tothe present invention there is provided on the outfeed side thereof acontrol device comprising frame 16, which includes opposed side members17 and a plurality of transverse members extending between the sidemembers and adapted to maintain them in generally parallel, spacedrelationship. Two such transverse members disposed at the entry end ofthe frame are guard plate 18 and bumper plate 19.

The frame 16 is movably supported by a plurality of wheels 20, which inturn are supported and guided by tracks 22 set in the work oor 12. Thetracks 22, as will be apparent, are disposed'below and parallel to theoutfeed path of the control apparatus, whereby the device may bepositionally adjusted therealong toward and away from the gangsaw,

Inside the frame and adjacent the bottom thereof is provided ahorizontally disposed conveyor 23. The conveyor comprises a pair oflongitudinally spaced transverse shafts 24 suitably journaled in theside members 17, each shaft carrying a pair of laterally andcorrespondingly spaced sprockets 25. A chain 26 engages each alignedpair of sprockets, and the chains are joined by a plurality oftransverse channels or cleats 27 joined thereto, the cleats extendingsubstantially the distance between frame side members and constitutingan open but relatively rigid conveyor platform. Between shafts 24, alongitudinally spaced pair of beams 28 extends transversely between theframe side members, bearing above them a pair of laterally spaced andlongitudinally extending slide bars 29, which extend substantially fromleading to trailing sprockets, although slightly off-set therefrom. Theslide bars 29 are adapted, as will be evident, to support the cleats 27on the upper ilight of the conveyor, and their ends are downwardlycurved, as at 30, to facilitate the passage of the cleats onto and olfthe slide bars.

One end of the trailing shaft 24 extends through the side member 17which supports it, and is engaged to a slip clutch 32, which in turn isdriven by a motor 33, in

' order to power the conveyor. The leading shaft 24 may befmounted intll'eside member slots 34 (see Figure l), and suitable means, such asthreaded bolts 35, may be provided to' vary the longitudinal positionthereof, whereby the tension'of the conveyor may be suitably adjusted.

i Above the entry yendr of the conveyor 'aplurality vof shafts 36 extendtransversely between the frame side members. These shafts, which in theillustrative embodiment are four in number, are spaced from each otherin both vertical and horizontal direction. As best shown in Figure 4,the shafts are stepped upwardly and rearwardly with respect to thematerial path, each successive shaft being offset slightly to the rearof the shaft below it. and offset vertically from the shaft below asomewhat greater distance.

From each shaft 36 depends a plurality of depending rigid fingers 37,each affixed at its upper end to a hub 38 by means of which it ispivotally suspended. The bank of fingers suspended from each shaft arearranged in side by side relationship, with minimum spacingtherebetween, to Vform a substantially continuous bank of individuallyacting fingers. The fingers may be constructed, for example, of one inchsquare bar stock, in which case if successive shafts 36 are offsethorizontally one inch, the successive banks will be parallel andcontiguous when the fingers hang in normal position unengaged by boards.

The lower end of each finger 37, preferably, is downwardly and forwardlyinclined, as at 39. The fingers of cach bank, that is the fingersdepending from each shaft 36, are of equal length, and the fingers ofthe different banks are of different lengths. The successive banks oflingers, from front to rear, are each longer than the preceding bank,enough longer so that their lower ends 39 extend into closer proximityto the conveyor 23, whereby the lower ends of the fingers are arrangedin transverse rows downwardly and rearwardly stepped.

Operation and function of the device will now be described in detail.First, the stabilizing apparatus will ordinarily be spaced from thegangsaw in accordance with the length of logs or cants to be sawed. Forrelatively short logs, the apparatus will be closely spaced, and forlonger logs the spacing will be correspondingly greater. The spacing maybe adjusted by moving the frame 16 on its wheels 20, and the device maybe locked at desired position on the tracks 22 in any conventionalmanner, as for example by means of blocks 21 clamped to the railsadjacent the frame wheels.

For operation, the motor 33 will be energized, its speed desir-ablybeing such as to drive the conveyor 23 at a speed somewhat exceeding thenormal work rate of the mill. With the conveyor 23 of the stabilizingdevice in operation, a log may be fed into and through the gangsaw li?,by means of an infeed carriage or otherwise. The outfed board bundlewill progressively extend from the gangsaw until the leading end thereofpasses below guard plate 18 and onto the conveyor 23 of the stabilizingdevice. The conveyor 23 rotates in the direction indicated by the arrowin Figure 4, and its cleats 27 rising on the forward end thereof willguide any depending boards upwardly onto the conveyor.

The boards in passing underneath the shafts 36 wilt cause some or all ofthe rigid fingers 37 to swing cr pivot rearwardly about the shafts fromwhich they depend, as indicated in Figures l and 4. The width of thefinger banks will normally correspond to the capacity of the mill, sothat a board bundle sawed from a log of maximum width which can behandled by the gangsaw 10 may displace all fingers of any bank, whereasa board bundle of lesser width may engage only central groups offingers. Similarly, the forward and shortest bank of fingers may be ofsuch length as to be engaged only by a board bundle of maximum depth,whereas a board bundle of lesser depth may engage only the rearwardthree banks of fingers. Normally, the approach of the rearward threebanks of fingers to the conveyor will be such that all are engaged by aboard bundle of average or customary depth.

The fingers 37 need not correspond in width or alignment to the boardsbeing sawed. Such alignment is not essential, since in any common casean individual board will contact at most two adjacent fingers of onebank, and an individual finger will contact at most two ad- .4 jacentboards. Each board may move freely in longitudinal direction under theline of fingers thereabove, the ngers in such case swinging freelyrearwardly and upwardly in pivotal manner. Under the influence ofgravity, the individually acting fingers will maintain close con tactwith the boards therebeneath, rising over high spots and falling intolow spots and generally following irregularities in such manner as toremain substantially constantly in contact with the board or boards.Accordingly, in passing below the shafts 36, each individual board willbe engaged by an aligned row of fingers, most or all of which will be inContact with the board at any instant of time.

The lower ends 39 of the rigid lingers 37 are formed so as to present tothe boards, when the fingers are displaced rearwardly, relatively sharppoints directed generally downwardly. While the boards may move freelyin longitudinal direction, any tendency of the boards to bounce upwardlycauses the finger ends to dig into the upper board edges, and preventsuch upward movement. The provision of multiple fingers in contact witheach board not only assures constant engagement, but also serves tospread the load when the board tends to bounce, thereby preventinggouging to any appreciable extent. Also, due to the relative dispositionof the shafts 36, the fingers of each successive bank will in the usualcase contact any individual board therebelow at a different angle,whereby vertical movement of the board is most positively precluded. Inthis manner, the boards are maintained in firm contact with the conveyor23, the fingers thereabove walking along the upper edges thereof toremain always in proper position to prevent'upward movement. When thetrailing end of a board bundle passes rearwardly beyond the reach of thefingers, they are free to fall under the influence of gravity to thehanging position illustrated in solid lines in Figure 4, ready to engagethe following board bundle.

In the manner described the outfed board bundle will be effectivelycontrolled and held steady at all times. The action of the stabilizingdevice is entirely automatic, depending only on gravity for itsoperation.

As will be evident, the device is adapted to function effectivelywithout adjustment or change, on logs or cants of all sizes and shapes.

The conveyor 23 of the device contributes somewhat to the outfeed of theboard bundle from the mill, and serves when the log being sawed leavesthe mill blades to transport the board bundle to the rear of thestabilizing device, from which position it may be conveyed away in anysuitable manner. The open construction of the conveyor permits bark andtrash to fall freely therethrough, into a pit or other receptacle, whichmay be provided.

It will thus be seen that there has been provided by this invention astructure in which the various objects hereinbefore set forth, togetherwith many practical advantages, are successfully achieved. As variouspossible embodiments may be made of the mechanical features of the aboveinvention, all without departing from the scope thereof, it is to beunderstood that all matter hereinbefore set forth or shown in theaccompanying drawings is to be interpreted as illustrative, and not in alimiting sense.

I claim:

l. Apparatus for stabilizing boards emerging from a gangsaw comprising aframe positioned beyond the saws and having transversely spaced slidemembers, a conveyor in said frame for supporting said boards, and aplurality of longitudinally offset banks of individually acting rigidfingers pivotally suspended between said side members, all fingers ofeach bank being of equal length and each successive rearward bank offingers extending into closer poximity to said conveyor.

2. Apparatus as defined in claim 1, wherein the outer ends of saidfingers are downwardly and forwardly inclined.

3. Apparatus for stabilizing boards emerging from a gangsaw comprising aframe positioned beyond the saws and having transversely spaced sidemembers, a conveyor in said frame, means for driving said conveyor, anda plurality of longitudinally oliset banks of individually acting rigidlingers pivotally suspended between said side members, all lingers ofeach bank being of equal length and each successive rearward bank oflingers extending into closer proximity to said conveyor.

4. Apparatus for stabilizing boards emerging from a gangsaw comprising aframe positioned beyond the saws and having transversely spaced sidemembers, a horizontal conveyor in said frame adapted to support andcarry said boards away from said gangsaw, means for driving saidconveyor, a plurality of shafts extending transversely between said sidemembers above the entry end of said conveyor, said shafts being steppedupwardly and rearwardly with respect to said conveyor, and a bank ofindividually acting rigid lingers pivotally suspended from each of saidshafts, all lingers of each bank being of equal length and eachsuccesssive rearward bank of lingers extending into closer proximity tosaid conveyor.

5. Apparatus as defined in claim 4, wherein the outer ends of saidlingers are downwardly and forwardly inclined.

6. In combination with a vertical, reciprocating gangsaw, a stabilizingdevice beyond the saws, and aligned with the outfeed path, of saidgangsaw, said stabilizing device comprising a frame having transverselyspaced side members, a conveyor in said frame disposed below the outfeedpath of said gangsaw, a plurality of longitudinally otl'set banks ofindividually acting rigid lingers pivotally suspended between said sidemembers over said conveyor, all lingers of each bank being of equallength and each successive rearward bank of lingers extending intocloser proximity to said conveyor, and means for adjusting the spacingbetween said stabilizing device and said gangsaw,

7. In combination with a vertical, reciprocating gangsaw, a stabilizingdevice beyond the saws, and aligned with the outfeed path, of saidgangsaw, said stabilizing device comprising a frame having transverselyspaced side members, a horizontal conveyor in said frame disposed belowthe ontleed path of said gangsaw and adapted to support and carry saidboards away from said gangsaw, means for driving said conveyor, aplurality of shafts extending transversely between said side membersabove the entry end of said conveyor, said shafts being stepped upwardlyand rearwardly with respect to said conveyor, and a bank of individuallyacting rigid lingers pivotally suspended from each of said shafts, allngers of each bank being of equal length and each successive rearwardbank of lingers extending into closer proximity to said conveyor.

8. Apparatus as delined in claim 7, wherein said conveyor drive means isadapted to drive said conveyor at a speed exceeding the normal work rateof said gangsaw.

References Cited in the lile of this patent UNITED STATES PATENTS142,294 Stowell Aug. 26, 1873 411,925 Linderman Oct. 1, 1889 697,565Thomas Apr. 15, 1902 901,889 Cummings Oct. 20, 1908 1,920,584 OsterburgAug. 1, 1933 2,073,898 Lof Mar. 16, 1937 2,160,307 Cleveland May 30,1939 FOREIGN PATENTS 56,229 Sweden Mar. 11, 1924

